lol, yeah, astrological. I knew there was something wrong there when I typed it.
However, I still don't agree that the Slow Down is not a warning telling you to slow down. It is basically warning you that you are going to fast for the FSD to be able to gracefully handle problems. So, if you get too close to that planet that you are zooming past, it's going to pull you out of supercruise painfully.
While I agree that the warning comes too late to be able to slow down without taking any other action (e.g. moving your nose away from the target), it most definitely is a warning suggesting that for safety you should slow down. Whether you do or not is up to you.